1. Field of the Invention
The present invention relates to an endoscope, a bending portion of which is bent in accordance with operation of an angle wire at an operation section.
2. Description of the Related Art
Conventionally, endoscopes configured to perform various inspections and treatments are widely known in medical and industrial fields. For example, among such endoscopes, medical endoscopes are widely used because the endoscopes are capable of acquiring in-vivo images of an inside of a body cavity without having to cut open a subject, such as a patient, by inserting a flexible elongated insertion section provided with a solid image pickup device at a distal end, and of performing medical treatment as necessary by causing a treatment instrument to protrude from the insertion section distal end.
The insertion section of such an endoscope includes, as internal components, a channel configured to enable insertion of treatment instruments, such as a biological forceps, an electric scalpel and an inspection probe, into the body cavity of a subject, a light guide configured to transmit illumination light, and a signal cable configured to transmit a signal from an image pickup unit provided at the distal end of the insertion section, for example. The internal components extend into an operation section which is continuously provided on a proximal end side of the insertion section.
Furthermore, to increase insertability and observation performance inside a subject, a bending portion is provided continuously to the insertion section of the endoscope, on a proximal end side of a distal end portion. Generally, an angle wire extending from the inside of the operation section to the inside of the insertion section is connected to the bending portion, and the bending portion is bent by pulling or relaxing of the angle wire by a bending knob, a bending lever or the like provided to the operation section (for example, see Japanese Patent Application Laid-Open Publication No. 2012-135515).